Art of drying varnished surfaces



1935- J. J. BROPHY ART OF DRYING VARNISHED SURFACES 3 Sheets-Sheet 1 Filed May 9, 1935' L EmEw 5338 Nqv. 12, 1935. .J. J. BROPHY 2,020,296

I ART OF DRYING VARNISHED SURFACES Filed May 9, 1955 s Sheets-Sheet 2 Ely- 2 I /84 v I ELM-l /Z2 lm mm NOV? 1935- J. J. BROPHY ART OF DRYING VARNISHED SURFACES Filed May 9, 195

3 Sheets-Sheet 5 Patented Nov. 12, 1935 UNITED STATES ART OF name VARNISHED summons John J. Brophy, Salem, Mass., assignor to The Turner Tanning Machinery Company, Fortland, Maine, a corporation of Maine Application May 9, 1933, Serial No.'6'l0,143

23 Claims.

suitable source in drying operations upon col-.

ored or coated surfaces on sheet material. 'Since radiation which falls perpendicularly, or substantially so, to the surface of the work is most effective; provision is made by my invention for so positioning and moving the work relatively to the source of ultra-violet radiation that a maximum proportion of the ultra-violet radiation strikes the varnished surfaces along lines perpendicular thereto. At the same time the spacing of the source of ultra-violet radiationwith respect to the" surface to'be treated is maintained as small as possible since the intensity of the effect of the radiation is greater the shorter the distance between said surface and the source of radiation. It is a further object of the invention to utilize the ultra-violet radiation to the maximum extent by keeping the work pieces in close juxtaposition to each other, it. being clear that radiation is wasted upon spaces between pieces of work as the latter travel past the source or sources of radiation.

With the above and other objects in view, and in accordance with an important feature of the invention, means is provided for moving pieces of work in a circular or cylindrical path around a source of ultra-violet radiation and at a minimum distance therefrom. As illustrated the described means comprises a flexible conveyor mechanism arranged to travel around a source of radiation in an arc of substantially 300 struck from the center of said source of radiation whereby as large aproportion as is practicable of the radiation strikes the varnished surfaces along lines perpendicular to said surfaces, this being the most effective radiation.

It is an important feature of the invention that means is provided for holding pieces of work in place upon the flexible conveyor without the use of fastening devices, the use of which would necessitate spacing between adjacent pieces of work, and the application of which would require the expenditure of considerable time and labor.

' the invention;

As illustrated the improved means comprises an air'suction apparatus whereby atmospheric pressure is depended upon for holding the work pieces in place, the conveyor being especially constructed for this purpose of foraminous material so that the work pieces may be held thereagainst through the operation of said air suction means.

In the illustrated machine, specially designed for the treatment of pieces of patent leather, the source of ultra-violet radiation is a horizontally arranged lamp to which the pieces of leather are presented by a horizontally traveling conveyor mechanism adapted to receive pieces of leather placed loosely thereon in close juxtaposition to each other, and to carry said pieces past the lamp in closely spaced relation thereto while the pieces of leather rest upon the conveyor un'- attached to each other or to the conveyor and free from any fastening devices. As illustrated, the horizontally arranged conveyor mechanism is guided and moved in such manner as to pass through an arc of substantially 300 with the lamp at the center axis thereof. As shown the lamp is located in a chamber from which the air may be withdrawn by means constantly operating to that end whereby each piece of leather, though free from the conveyor, is held stationary with respect to the conveyor in fully spread out condition thereon during all of its travel about the lamp.

These and other important characteristics and features of the invention and novel combinations of parts will now be described in detail in the specification and then pointed out more particularly in the appended claims.

In the drawings, p

Fig. 1 is a view in side elevation and partly in: section of a machine showing one embodiment of V In the illustrated machine, which is particularly designedfor treating patent leather surfaces, there is provided a horizontally arranged lamp l0 conveniently of the type known as a gaseous discharge lamp energized by induction and operating on a high tension current. The

lamp tube is of quartz and is sealed after introducing a small amount of mercury, to serve as the active agentin producing the ultra-violet radiation, and a small amount of argon at the properpressure to assist in starting ionization of the mercury vapor. At one end of the lamp I8 is a coil II for carrying water to keep the temperature of the lamp down and to maintain gas pressure at a value for eihcient operation of the lamp. Surrounding the lamp l8' is a quartz envelope l2 cylindrical in form and open to the air at each end. The purpose of this envelope be described later in the specification. Outside of the envelope I2 is a coiled copper tube l4 serving as an inductor element, the-tube l4 being a long ellipse in cross section so as to leave as much space as possible between the turns of the coil. The purpose of this copper coil is to carry 8 a high frequency current from an oscillation generator, not shown, the action'of this coil being to induce current in the gases of the lamp.

In the illustrated machine, which has operated effectively and satisfactorily in practice, the lamp inductor coil I4 is about sixty inches long and comprises one hundred twenty equally spaced turns, the conductor being made of copper tube flattened into an ellipse in cmss section and current from the oscillation generator, satisfactory operation having been secured in practice with a frequency of about 12,000 kilocycles, an

tration only and may be varied according to cir-' cumstances to secure-the most effective and effi- :cient operation under any given conditions. I

believe that the maximum efficiency of the apparatus is secured under normal conditions .when the impedance of the lamp inductor circuit approximates as closely as possible that of the oscillator tubes. I also believe that, in conducting the high frequency current from the oscillation generator to the lamp inductor coil, more eillcient operation can be secured by using flat parallel conductors. This willtend to avoid local inductive effect.

The energy parted to the lamp produces ultra-violet radiation. This lamp, operated as above indicated, is particularly eflicient since the greater part of the ultra-violet radiation there- 'from falls within a relatively narrow band extending from about 2500 to 3500 Angstrom units,

radiation within this band being the most eflective in the treatment of varnished surfaces to dry the same. Furthermore, there is relatively little radiation in the longer wave lengths manifested as heat. The copper coil I4 is a tube which.

carries a constantly flowing stream of water in order to prevent the copper from being'melted by the relatively intense heatwhich otherwise would be developed in this copper conductor. As shown the copper coil l4 has its terminals l8 and I8 arranged in parallelism as shown in Fig. 3.

In order to utilizeultra-violet radiation to the best advantage it is desirable that as large a proportion as possible of such-radiation should strike the varnished surface to be treated along lines perpendicular thereto, as indicated in Fig. 5, wherein lines 81 indicate the direction of radiation from lamp l8 to the varnished surface of a piece of work 39 traveling in a circular path about said lamp. For this reason means is provided for moving the pieces of work around the lamp in a path which is an almost closed cylinder, that is, as illustrated, through an arc of about 300. As shown, this means com- 5 tables 58, 5| said shafts carrying rollers 52 15 I which extend the full width of the machine and serve as supports and feeding means for the wire mesh portion 42 of the conveyor whilethe sprockets, serve as supports and feeding means for the link chains 44 at each edge of 20 the mesh. In addition to passing around the sprockets '46 the link-chains 44 are also engaged with a pair of sprocket wheels 54 (Fig. 1) upon shafts 56 and with a larger sprocket wheel 58' (Figs. 1 and 4) by which the conveyor is carried 25 in a cylindrical path the axis of which corresponds to the axis of the lamp I8, the sprockets 54 co-operating with the larger sprockets 58 to guide the link chains and the attached woven wire mesh 42 along a path which approaches 30 as near as is practicable to a closed cylinder of about ten inches in diameter. Conveniently and as shown, the sprocket wheel 58 at each end of the lamp chamber consists of an annular member having sprocket teeth upon its outer periph- 35 ery, the inner periphery of said annular member being receivable within a groove in a stationary supporting member 88 (Figs. 3 and 4) made preferably of a non-conducting substance such as bakelite, said member 88 being attached 40 to wooden struts 82 constituting part of the machine frame; Upon reference to Fig. 4 of the drawings it will be observed that the conveyor 48 is an endless conveyor and that it is guided in the lower run thereof by idler rollers 18 also mounted in the machine frame and extending clear across from one side thereof to the other. e

Means is provided for driving the shafts 48, 49, the said means comprising in the illustrated con- 50 struction an electric motor 12 (Figs. 1 and 2) having an armature shaft 14 provided with a worm 18 arranged in mesh with a worm gear I8 mounted upon a shaft 88 supported inthe niachine frame. Fastened to the said shaft 88 is a sprocket wheel 82 around which passes a sprocket chain 84 also engaged with a sprocket 86 on a shaft 88 to which is fixed a second sprocket wheel 98 about which passes asprocket chain 92 which passes around a larger sprocket wheel leather upon the wire mesh conveyor 48 while it is traveling in reverse curves around the lamp l8, said means comprising in the illustrated construction an air suction chamber H8, the walls I I 2 of which are made of sheet metal, as most 7 at I26 (Fig. 4) at opposite ends thereof. 25,

clearly shown in Fig. 4. Preferably and as shown an upper wall II4 of the chamber H0 is con-1 shape of the leather in place upon the wire mesh ,ccnveyor.

To provide a suction effect for the purpose of holding pieces of leather upon the mesh conveyor there is provided means for withdrawing air from the chamber I I0, the said means comprising. a blower I (Figs. 1 and 2) having a conduit I22 extending therefrom, said conduit dividing into two pipes I24, the pipes I24 opening into opposite ends of the chamber H0 at opposite sides of the machine. Upon reference to Figs. 3 and 4 it will be seen that the pipes I24 open into a lower part of the chamber IIO as The air pressure upon the pieces of leather traveling along the wire mesh conveyor 40 is sufficientto' hold them firmly on the conveyor while they are passing around the lamp I0.

For conveying pieces of leather to the described wire mesh conveyor 40, there is provided a feeding mechanism comprising a plurality of relatively narrow belts I30 (Figs. 1 and 2) the upper run of which rests upon the table 50, the belts I 38 passing around crown portions I 34 of an idler roll I36. At their other ends the belts I30 pass over crown portions I38 of a driven roll I40 mounted'upon the frame of the machine and having fixed thereto at one end a sprocket wheel I42 (Fig. 1) arranged to be driven by a sprocket chain I44 passing over a sprocket I46 onthe driven shaft 49 around the roller 52 of which the wire mesh conveyor passes. For guiding the pieces of work from the conveyor belts I30 to the wire mesh conveyor 40 there is provided (Figs. 2 and 4) a short table I50. 4

Conveniently, and as shown, a delivery mechanism is provided for carrying the pieces of work away from the wire mesh conveyor 40 after treatment by the lamp I0, the said delivery mechanism comprising a short delivery table I52 and belts I 60 (Figs. 1 and 2) passing over the table ."5I and driven by crownedportions I64 of a roller I66; the shaft I60 (Fig. 1)of which carries a sprocket I10 arranged to be driven by a sprocket chain I12 in turn driven by a sprocket I14 on the .driven shaft 40. At their other ends the belts I60 pass over crown portions I80 of an idler roll I82 rotatably mounted in the frame of the machine. Both the sets of belts I30 and I60 may be provided with belt tight'eners-such as thepivoted members I84 (Figs. 1 and 2) carrying at their ends idler rolls I86 arranged to rest upon the lower runs of the belts.

In the manufacture of patent leather 8. daub coat is applied to a piece of leather while the latter maintaified in stretched condition on a frame. This first daub coat may be allowed to dry although it is usually baked in an oven. Subsequently several other daub coats are applied and the baking repeated with each coat. Finally a finish" coat of varnish is applied and the leather placed in an oven where it is baked usually for a period of. fourteen hours or more at a temperature of about 160 F. Following this operation it has been common practice to "subject the patent leather surfaces to solarizing in the open air, the purpose being to complete the drying of the varnished surfaces to such an extent at least as to reduce to the desired degree 5 the sticky or tacky condition which persists even after prolonged baking. Since the daub and varnish coats of different batches of patent leather vary considerably, even in the same plant, the treatment of the varnished surfaces by ultra- 10 violet radiation from natural or from artificial sources must becarried out for various periods of time. Hence in the illustrated machine means is provided for driving the conveyor mechanism left between the ends of the are through which ultra-violet radiation might escape without having performed any useful purpose. To obviate this possible loss of radiation there is provided, in the illustrated construction, a reflecting surface arranged to reflect radiation back upon the varnished surfaces of the leather pieces passing through the chamber surrounding the lamp I0.

' Conveniently, the reflecting surface is provided by two members I90, I92, each having a polished surface adapted to reflect radiation to the leather as described. The polished surface may be made of chromium or of a specially prepared aluminum. While the reflectors I90, I92 may be supported in any convenient manner they are shown attached to a member I94 which extends vertically into the lamp chamber and which may also serve as a supporting means for the lamp I0. As shown, the envelope or shield I2 is attached to the supporting member I94, the lamp I0 being supported within the shield I2 by means of properly spaced abutments I96 which may be made of quartz, similar to that used in the manufacture of the shield I2.

In operating the illustrated machine a pieceof work is placed upon the belts I30 passing over the table 50. Since all pieces of patent leather are substantially flat when placed upon a flat supporting surface, only'a. moderate amount of care is necessary in placing the work on the table to insure that it is spread out flat without any folds therein. The piece of work is promptly carried to the wire mesh conveyor 40 which op,- erates to carry each piece of work around the lamp I0 with its varnished surface facing toward the lamp during all of its travel through an arc of about 300 around the lamp I0 .during which the varnished surface is subjected to ultra-violet radiation from the lamp, a great portion of which 1 falls upon the work along/lines perpendicular to the varnished surface, a small portion of the radiation being reflected upon the work by the v-shaped'mirro r placed above the lamp at the point where the workenters and leaves the lanip chamber. Following its passagearound the lamp each piece of leather is delivered to the set of belts I60 passing over the table 5| whereby the a ork is delivered .to the operator at the rear of t e machine.

Having described my invention/what I claim simultaneously therewith moving said sheet ma- ,terial in a cylindrical path about a source of ultra-violet radiation located at the axis of said cylindrical path, whereby radiation from. said source will strike all portions of the exposed surface of the sheet material substantially perpendicularly thereto.

2. In a machine for treating varnished surfaceson flexible sheet material by ultra-violet radiation, .a lamp serving as a source of ultra-violet radiation, and means to move flexible sheet material in a circular path around the'lamp andsimultaneously therewith cause it to conform to said circular path in such manner that all points in the exposed surface of the sheet material are substantially equidistant from the lamp, said means being constructed and arranged to interpose no obstruction between the lamp and the surface to be treated during its travel around the lamp.

3. In a machine for treating varnished surfaces on flexible pieces of leather by ultra-violet radiation, a lamp serving as a source of ultraviolet radiation, a circular guideway having said lamp located at its longitudinal axis, and means to move flexible pieces of varnished leather along said guideway and simultaneously therewith cause the leather to conform to a circular path around the lamp in such manner that radiation from the lamp will strike all portions of the exposed surfaces of the leather pieces substantially perpendicularly thereto, said means being constructed and arranged to engage the unvarnished surface only of each piece of leather thereby to interpose no obstruction between the lamp and the surface to be treated during its travel around the lamp.

4. In a machine for treating varnished surfaces on flexible sheet material by ultra-violet radiation, a lamp serving as a source of ultraviolet radiation, a chamber having a stationary cylindrical wall enclosing said lamp, the lamp being located at the longitudinal axis of the cylindrical wall, and means to move the sheet material in a cylindrical path over and along the inside surface of said cylindrical wall and to maintain said material in uniformly spaced relaviolet radiation, a chamber having a stationary cylindrical wall enclosing said lamp, the lamp being located at the longitudinal axis of the cylindrical wall, a flexible conveyor to move sheet material over and along the inside surface of said cylindrical wall, said flexible conveyor being maintained in uniformly spaced relation to'said inside surface, and means to hold the sheet material conformably to the inner concave surface of the flexible conveyor, so that said material is carried in a cylindrical path around said lamp,

' whereby all points in the exposed surface of said sheet material are maintained substantially equiforaminous conveyor for carrying sheet material faces on flexible sheet material by ultra-violet radiation, a horizontally arranged lamp serving as a source of ultra-violet radiation, means comprising a flexible conveyor to move pieces of varnished leather in a cylindrical path around the 5 lamp, said means having a horizontally arranged portion arranged to transport and to deliver pieces of leather unattached thereto to said flexible conveyor, the latter being constructed and arranged to receive said unattached pieces of leather, and means to hold the pieces of leather in place on said flexible conveyor while they are being carried in succession around said lamp, said holding means being constructed and arranged to maintain the pieces of leather parallel to said conveyor while in said cylindrical path, whereby all portions of the leather are equally spaced from the lamp while travelling around said. lamp, said holding means being further constructed and arranged to interpose no obstruction between the lamp and any portion of the varnished surfaces to be treated.

- tion, a lamp serving as a source of ultra-violet radiation, means including a flexible and foraminous conveyor arranged to travel in a cylindrical path about said lamp for carrying sheet material in said cylindrical path around the lamp, and means co-operating with the foraminous conveyor for holding such sheet material conformably to the concave surface of the cylindrically arranged conveyor so that the concavely curved surface of the sheet material is directly exposed to radiation from said lamp.

8. In a machine for treating varnished surfaces on flexible sheet material by ultra-violet radiation, a lamp serving as a source of ultraviolet radiation, a flexible conveyor for carrying pieces of varnished leather'in a cylindrical path 40 around the lamp, said conveyor including a foraminous sheet of material upon which the pieces of leather are successively supported, said foraminous sheet being arranged in cylindrical form about the lamp as a central axis, and means co-operating with said foraminous sheet of the conveyor for holding the pieces of work on and everywhere in contact with the concave surface of the cylindrically arranged foraminous sheet so that said pieces of work are exposed uniformly to radiation from said lamp.

9. In a machine for treating varnished surfaces on flexible sheet material by ultra-violet radiation, a lamp serving as a source of ultraviolet radiation, means comprising a flexible and in a cylindrical path around the lamp, the conveyor being so arranged with respect to the lamp that every point in the exposed surface of the sheet material is equidistant from said lamp-during travel of the material in said path, and air suction means operative to hold sheet material in place upon said foraminous conveyor while said sheet material is being carried in the cylindrical path around the lamp.

10. In a machine for treating varnished surfaces on flexible sheet material by ultra-violet radiation, a lamp serving as-a source of ultraviolet radiation, a chamber for said lamp having a wall of foraminous sheet material arranged in cylindrical form with the lamp at the longitudinal axis thereof, a flexible and foraminous conveyor movable over said wall in a cylindrical path and arranged to move a piece of work into and out of said chamber and around said lamp,

cylindrical path, andmeans for withdrawing air I through the foraminous wall and foraminous conveyor, thereby to hold the piece of work upon the conveyor while the latter is passing in the cylindrical path through the lamp chamber.

11. In a machine for treating varnished surfaces on flexible sheet material by ultra-violet radiation, a lamp serving as a source of ultraviolet radiation. a chamber for said lamp having ""a'wall'of foraminous sheet material arranged in cylindrical form with the lamp at the longitudinal, axis thereof, a flexible and foraminous conveyor movable over said wall in a cylindrical path and arranged to move a piece of work into and out of said chamber and around said lamp, whereby every point in the piece of work is equidistant from the lamp during its travel in said cylindrical path, a chamber enclosing the lamp chamber, and means for withdrawing air from the last-named chamber whereby the.tendency to withdraw air from the lamp chamber through the foraminous wall thereof has the effect of holding the piece of work firmly upon the supporting surface of the foraminous conveyor during its travel in the cylindrical path through the lamp chamber.

12. In a machine for treating varnished surfaces on flexible sheet material by ultra-violet ralindrical path, whereby all portions'of the work under o ng treatment are equally spaced from said lamp while said portions are disposed on the la t-mentioned part of the conveyor mechanism during movement of the latter-about said lamp.

13. In a machine for treating varnished surfaces on flexible sheet material by ultra- -violet radiation, a horizontally arranged lamp serving a a source of ultra-violet radiation, 2. conveyor having a horizontal run upon which pieces of work may be loosely placed in close juxtaposition to each other, a flexible conveyor to receive pieces of work from the first mentioned conveyor and constructed and arranged to move alonga cylin-' drieal path about said lamp and to carry pieces of work throughout said cylindrical path, and means progressively operative during travel of the work in said cylindrical path to hold the pieces of work parallel to said conveyor while in said cylindrical path, whereby all portions of the work undergoing treatment are equallyspaced from said lamp while said portions are disposed on the last-mentioned part of the conveyor during movement of the latter about said lamp, and a delivery means to receive the pieces of work as each in turn is progressively released by the holding means associated with the flexible conveyor.

14. In a machine for treating varnished surfaces on sheet material by ultra-violet radiation,

ahorizontally arranged lamp serving as a source of ultra-violet radiation, a horizontal conveyor adapted to receive pieces of work held in place thereon by gravity only, a second conveyor-arranged to receive said pieces of work from the first conveyor and to carry them in succession in .a cylindrical path about said horizontally arranged lamp, the second cc-nveyor including a sheet of flexible and foraminous material to support the pieces of work, and air suction means operative to hold the pieces of work against the foraminous sheet portion of the second conveyor while the pieces of work are passing around said lamp. Y

15. In a machine'for treating varnished surfaces on flexible sheet material by ultra-violet radiation, a lamp 'servingas a source ofultraviolet radiation, a flexible conveyor arranged to carry such sheet material in an arc of substantially more than 180 about said lamp, and means to cause said material to conform to the arc while being carried around the lamp, whereby every point in the sheet material is equidistant from the lamp during the travel of the material in said are.

16. In a machine for treating varnished surfaces on sheet material by ultra-violet radiation, a lamp serving as a source of ultra-violet, radiation, means comprising a flexible conveyor to carry a piece of work through an arc of substantially 300 about said lamp, air suction means for holding thepieces of work upon said conveyor.- and a mirror arranged substantially to close the space between the ends of said arc, thereby limiting the amount of air entering into the space about the lamp while at the same time serving as a reflector to direct ultra-violet radiation upon the lamp to expose surfacesof said materi l equidistantly with respect to the source of ultra-violet radiation, said conveyor including a flexible sheet of foraminous material. reinforc ng members at .oppositeedges of .theflexiblc-foraminous sheet,

said reinforcing members and said sheet being se- 18. In a machine for treating varnished 'surfaces on flexible sheet material by ultra-violet radiation, a lamp serving as a source of ultraviolet radiation, a conveyor arranged to carry sheet material in a cylindrical path about said lamp to expose surfaces of said material to'ultraviolet radiation, said lamp beingloceted at=the longitudinal axis of said cylindrical path, so that every point in the piece of work is equidistant from the lamp during its travel in said path, said conveyor including a flexible sheet of foraminous material, a chamber about the lamp having a cylindrical wall of foraminous material,

means guiding the flexibie sheet portion of the conveyor over the inside concave surface of said cylindrical wall, a chamber enclosing the firstmentioned chamber, and means for withdrawing conveyor during travel of the latter in the said cylindrical path.

19. In a machine for treating varnished surfaces on flexible sheet material by ultra-violet radiation, a lamp serving as a source of ultratending through an arc of approximately 300 about the lamp, said lamp being located at the center of said arc, means to guide the flexible sheet portion of the conveyor over the inside concave surface of said foraminous wall so that all portions of the work are equidistant from the lamp during travel in said arc, a chamber enclosing the first-mentioned chamber, and means for withdrawing air from the last-mentioned chamber.

20. In a machine for treating varnished surfaces on sheet material by ultra-violet radiation, a horizontally arranged lamp, a flexible conveyor having a portion thereof movable in a cylindrical path about said lamp as a central axis, means associated with the conveyor to hold the sheet material concentrically disposed to said cylindrical path so that the exposed surface of the sheet material is everywhere the same distance from the lamp throughout the cylindrical path of its travel about the lamp, said holding means being operative to release the sheet material as the flexible conveyor changes its direction after passing through said cylindrical path, and a delivery means for receiving the sheet material from said flexible conveyor as it is released by the holding means in association with said flexible conveyor.

21. In a machine for treating varnished surfaces on sheet material by ultra-violet radiation, a horizontally arranged lamp, a flexible conveyor having a portion thereof movable in a cylindrical path about said lamp as a central axis, suction means associated with said flexible conveyor and operative to hold the sheet material concentrically disposed upon the conveyor during travel of the latter through said cylindrical path about the lamp, whereby the exposed surface of the sheet material is everywhere the same distance from the lamp throughout the cylindrical path of travel of the material, said suction means serving also to hold the material on the flexible conveyor flexible conveyor and then to release said material progressively during travel of the latter, and a delivery means to which the flexible conveyor delivers the sheet material as it is progressively released from the actionof the suction means. 5

22. In a machine fortreating varnished surfaces on sheet material by ultra-violet radiation, a horizontally arranged lamp, a flexible conveyor having a portion thereof movable in a cylindrical path about said lamp as a central axis, a conveyor having a horizontal run upon which pieces of sheet material may be loosely placed to be carried to said flexible conveyor, suction means for holding the sheet material concentrically disposed upon the flexible conveyor while the latter is pass- 15 ing through said cylindrical path about the lamp, whereby the exposed surface of the sheet material is everywhere the same distance from the lamp throughout the cylindrical path of travel of the material, said suction means being arranged to 20- release the material progressively during travel of the latter, and a delivery conveyor having a horizontal run positioned to receive the pieces of sheet material as they are progressively discharged from said flexible conveyor and from 25 the suction means in association therewith.

23. In a machine for treating varnished surfaces on sheet material by ultra-violet radiation, a horizontally arranged lamp, a flexible conveyor having a portion thereof movable in a cylindrical 30 path about said lamp as a central axis, a conveyor having a horizontal run upon which pieces of sheet material may be loosely placed to be fed to said flexible conveyor, suction means for holding the sheet material concentrically disposed upon 35 the flexible conveyor while the latter is passing through said cylindrical path about the lamp, whereby the exposed surface of the sheet material is everywhere the same distance from the lamp throughout the cylindrical path of travel of 40 the material, said suction means being arranged to release the sheet material progressively during travel of the latter, a delivery conveyor having a horizontal run positioned to receive the pieces of sheet material as they are progressively dis- 4:;

charged from said flexible conveyor and from the suction means in association therewith, a transfer table located between said flexible conveyor and the horizontal run of the feeding-in conveyor, and a second table between said flexible conveyor and the horizontal run of the delivery conveyor.

com: J. BROPHYI. 

